Macduff and Malcolm both use literary devices to express their despair.
Malcolm is upset because his father was killed and he has been chased from the throne. Macduff is upset because his wife, son, and entire family has been slaughtered by the evil tyrant Macbeth.
Malcolm begins by using hyperbole, a type of figurative language that involves exaggeration.
Let us seek out some desolate shade and there
Weep our sad bosoms empty. (Act 4, Scene 3)
Macduff also speaks in eloquent grief, such as when he describes his reaction to his family’s death.
All my pretty ones?
Did you say all? O hell-kite! All?
What, all my pretty chickens and their dam
At one fell swoop?(255) (Act 4, Scene 3)
It humanizes and infantalizes Macduff to refer to his children as "chickens."
The beauty of this scene is that no matter how much Malcolm tries to tempt Macduff, Macduff proves loyal. Malcolm also proves to be both a good friend for Macduff and a strong leader, because he helps him channel his grief into rage.